Pump



E. EGGER PUIIP 6 Sheets-Sheet 1 Filed Feb. 19, 1962 me 2w WW ME 6 y 0 ,MN -UMHM m m m 8 G. I \vN v 9 W 3 is Q r P I I Y a H WM U 3 E. EGGERMarch 2, 1965 PUMP 6 Sheets-Sheet 2 Filed Feb. .19, 1962 E. EGGER March2, 1965 PUMP 6 Sheets-Sheet 3 Filed Feb. 19, 1962 7 ill/[III] [1a.

INVENTOR. EMILE/Essa BY Array/vars March 2, 1965 E. EGGER 3,171,357.

PUMP

Filed Feb. 19, 1962 e Sheets-Sheet 5 March 2, 1965 E. EGGER 3, 7 ,3 7.

PUMP

Filed Feb. 19, 1962 6 Sheets-Sheet 6 ".5; Tmllnmln" INVENTOR. 5 1w [GGEof the impeller.

United States Patent Office 3,171,353 ?a.tented Mar. 2, 1965 ,349/61 seClaims. (Cl. ins-103 The present invention relates generally to a pumpdevice and more particularly to an improved apparatus for pumping afluid containing foreign material or bodies of an appreciable size.

In the pumping of fluids such as the liquids encountered in industrialprocesses and the liquids encountered in municipal sewerage systems, theproblem arises of handling such fluids without clogging or damaging thepumping apparatus due to the quantity of foreign substances which arecontained in the fluids. processes the need arises for a pump which canhandle liquids which are made up of solid substances entrained in aliquid. In other applications fluid used as a vehicle to carry solidsubstances must be pumped. In certain applications where a fluid is usedas a vehicle to carry other substances, clogging may not be the onlyproblem but in addition there may be the problem of preventing thesubstances from being damaged or destroyed by passing into contact withmoving portions of the pumping apparatus. 7

In connection with these problems centrifugal pumps have been designedwhich are provided with a substantially open passage from the inlet tothe outlet of the pump so that large solid substances can pass throughthe pump without causing clogging. In pumps of this type the centrifugalimpeller is located at the side of the pump casing opposite to the pumpinlet so that the flow passage is unobstructed and the substances in thefluid are less likely to strike the impeller. Pumps of this type operatealong the conventional centrifugal pump principles wherein fluid passestoward the center of rotation of the impeller and then is acceleratedradially outwardly along the impeller and finally hurled from theperiphery of the impeller into the outer regions of the pump casing. Thefluid being thrown from the impeller enters the outer portions of thecasing and moves toward the pump outlet. This flow of fluid toward theouter portion of the pump casing engages fluid in that region of thecasing and carries it toward the outlet. The large clearances in such apump which are necessary to prevent clogging have a detrimental effectupon the efliciency of the pump and the maximum head which the pump canproduce since the large clearance between the fluid in the casing andthe impeller prevents effective control of the fluid by the impeller.Thus only the fluid which passes through the inlet to the center of theimpeller and is subsequently hurled from the rim of the impeller intothe outer regions of the casing is effectively under control Theremainder of the fluid in the casing is engaged adjacent its peripheryby the flow moving outwardly in a conical pattern from the impeller andis moved toward the outlet. Since the outward flow from the impeller isat a high velocity and meets the low velocity fluid adjacent theperiphery of the chamber, it causes turbulence which results in energylosses and inefliciency. Because of the appreciable flow of fluidpassing along the impeller in the prior non-clog pumps, the impeller isnot protected from wear or damage by foreign substances. The flow intothe center of the impeller results in impact of the foreign substancesdirectly upon the impeller before they are swept toward the pump outlet.The overall result of previous eflorts In some industrial to provide anon-clog pump have been to prevent clogging at the expense of theoperating characteristics of the pump.

Accordingly it is the primary object of the present invention to providea pump which is capable of handling fluids containing foreign substanceswithout clogging and which at the same time is capable of operating inan eflicient manner and capable of producing high flow at high pressureheads.

More particularly it is an object of the invention to provide a pumpincluding large clearances within the pump passage and further includingan impeller capable of forming a circulation of fluid with respectthereto which is adapted to engage or couple the remaining portion ofthe fiuid in the casing and to urge it to the outlet of the pump.

Furthermore it is an object of the invention to provide a pump in whichthe flow of fluid from the impeller is diverted back toward the impellerin order to form an effective coupling with the fluid passing throughthe pump.

Another object of the invention is to provide a pump having asubstantially open passage in order to prevent clogging.

Also an object of the invention is to provide a pump sealing arrangementwhich is conditioned to prevent leakage whether there is a substantialpositive or negative pressure within the pump casing adjacent to theshaft connected to the pump impeller.

A still further object of the invention is to provide a sealingarrangement in which the magnitude of closure forces between the sealingmembers are related to the pressure conditions adjacent to the sealingarrangement and to the rotational speed of the impeller.

It is also an object of the invention to provide a pump which minimizesthe contact of foreign substances in the fluid from striking theimpeller.

In addition it is an object of the invention to provide a pump with anopen passage and adapted to provide a high head with high efficiency.

In accordance with the principles of our invention, the device comprisesa rotary impeller having an axis about which it rotates and forming awall rotating about the axis and extending radially therefrom. Bladesextend laterally from the wall at an angle with respect to its rotatingdirection and rotate therewith. The device further includes structureforming a chamber laterally offset from the wall and entirely openthereto and to all of its blades and to full circumferential flow. Thechamber is adapted to confine fluid with the wall and the bladesimmersed therein. Rotation of the impeller normally causes the blades toforce the fluid to flow in the radially extending direction of the walllengthwise with respect to the blades while rotating in their rotatingdirection. Rotation of the impeller further causes fluid to bedischarged from the blades ends. Means are located adjacent to the endsof the blades for diverting the fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofthe blades in paths oifset from the flow in the radially extendingdirection of the wall between the latter flow and the fluid in thechamber. In this Way there is formed a toruslike flow of fluid rotatingabout the axis while flowing recirculatingly, continuously and laterallywith respect to its rotation. Thus there is formed in effect a fluidimpeller engaging the fluid in the chamber. The structure forms a fluidinlet and outlet for the chamber which are respectively located topermit fluid to feed from outside of the chamber to the flow establishedby the fluid torus and to permit this flow to discharge to the outside.

In one embodiment of the invention the chamber is substantiallycylindrical in form. The rotary impeller which is substantially in theform of a disc is disposed adjacent the inner surface of the chamber.The impeller includes a plurality of blades which extend towards itsperiphery. About the periphery of the impeller is disposed a shroudmember which substantially diverts the movement of fluid with respect tothe blades and reverses it toward the central portion of the impeller.The diverting of the fluid causes recirculation of the fluid withrespect to the blades which forms a close coupling to the remainder ofthe fluid in the chamber and urges the fluid to passfrom the chamber.The shroud member for reversing the movement of the fluid may be mountedupon the impeller itself or may be mounted upon the chamber adjacent tothe periphery of the impeller.

In another embodiment of the invention the pumping chamber as well asthe impeller are in a substantially tapered form. This form reduces theturning of the solid substances in the fluid when the fluid is passingthrough the pumping chamber. The tapered impeller has a plurality ofvanes for causing movement of the fluid with respect to the impeller. Ashroud member either on the impeller or on the chamber adjacent to theperiphery of the impeller diverts the movement of fluid so thatcirculation is established with respect to the impeller. The circulationforms a close coupling to fluid in the tapered chamber and urges it topass through the chamber.

In still a further embodiment of the invention the pump includes animpeller having a substantially elongated form. The elongated impellermay be in the form of a hollow cylinder having a plurality of bladesdisposed along its inner surface. The vanes which can be arranged in anaxial manner with respect to the axis of rotation of the impeller movethe fluid adjacent the vanes toward one of the end portions. Adjacentthe end portion either on the impeller or on the chamber adjacent to theimpeller is a shroud member which diverts the movement of the fluid withrespect to the impeller. The diverting of the fluid establishesrecirculation with respect to the blades which in turn couples with thefluid in the chamber and the interior of the impeller. The coupling ofthe circulating fluid drives the fluid axially through the device.

In still another embodiment of the invention the device includes asealing arrangement for the impeller shaft which is responsive to thepressure adjacent to it for determining the sealing pressure.

In a further embodiment of the invention the device includes a sealingarrangement for the impeller shaft which is responsive to the rotationalspeed of the impeller for determining the sealing pressure.

Prior pumps operating under centrifugal conditions and adapted toprevent clogging have employed impellers offset from the main flowpassage and adapted to hurl the fluid from the periphery of the impelleroutwardly toward the outer peripheral portion of the chamber. Thisarrangement results in only a portion of the fluid in the chamber beingengaged by the fluid passing from the periphery of the impeller and isalso accompanied by turbulence due to the intersection of the highvelocity fluid from the impeller with the lower velocity fluid withinthe chamber. As opposed to these prior art constructions the device ofthe invention diverts the flow from the impeller to move in a directionopposite to that of the prior art pumps, that is to be diverted towardthe axis of rotation of the impeller in order to establish recirculationof the fluid with respect to the impeller. The recirculation forms atorus-like body of fluid adjacent the impeller and having fluid bladeswhich form an excellent coupling to the fluid in the passage adjacent tothe impeller. The fluid blades engage the fluid in the passagesubstantially across the portion of the passage adjacent to the impellerso that the fluid in the passage can be rotated with high efficiency.The coupling of the fluid in this manner enables the pump of theinvention to produce higher pressure heads than those obtained with theprior pumps having the same impeller diameter.

Furthermore the establishment of the recirculating fluid adjacent theimpeller forms a barrier of flow which can deflect foreign substances inthe fluid from contacting the impeller. Thus the pump of the inventionis adapted to handle fluids such as wood pulp suspended in a liquid,mixtures of water and gravel or sand in dredging operations, seweragecontaining solids, fragile articles such as fruit, vegetables and thelike suspended in liquids, and solid articles such as coal suspended inliquids. The pump of the invention is also adapted to handle gases suchas a flow of air for conveying substances suspended therein.

Other objects and features of the invention will become apparent in thefollowing specification and claims and in the drawings in which;

FIG. 1 is an axial section View of one embodiment of the invention;

FIG. 2 is a radial section view of one embodiment of the invention;

FIG. 3 is an enlarged section view taken along the lines 3-3 in FIG. 2;

FIG. 4 is a fragmentary view of the end portions of the pump blades;

FIG. 5A is a fragmentary axial section showing a stationary shroudadjacent the impeller;

FIG. 5B is a section view showing an impeller with curved blades;

FIG. 6A is a fragmentary axial section view showing an impeller providedwith a rotating shroud;

FIG. 6B is a section view of an impeller having radial blades;

FIG. 7 is a section view taken along the line 7-7 in FIG. 8 showing animpeller with a rotating shroud and having a ring member intersectingthe blades;

FIG. 8 is a section view showing the face of an impeller having arotating shroud and a ring member intersecting the blades;

FIG. 9 is a section view of an impeller having curved blades disposed ina direction opposite to that of FIG. 5B;

FIG. 10 is a section view of an embodiment of the invention in which thechamber and the impeller are of a substantially tapered shape;

FIG. 11A is an axial section view of an embodiment of the invention inwhich the pump contains a hollow cylindrical impeller;

FIG. 11B is a radial section view of an embodiment of the invention inwhich the pump has a hollow cylindrical impeller;

FIG. 12 is a fragmentary axial section view showing a membrane seal foran impeller;

FIG. 13 is a fragmentary axial section view showing a diaphragm seal foran impeller;

FIG. 14 is a fragmentary section view showing a further embodiment of animpeller seal;

FIG. 15A is a fragmentary axial section view of an impeller having arotating shroud;

FIG. 15B is a radial section view of an impeller having radiallydisposed blades;

FIG. 16A shows another embodiment of an impeller seal of the diaphragmtype;

FIG. 16B is a section view of the diaphragm spring of the impeller sealof the invention;

FIG. 17A is a fragmentary section view showing the blades inclined to animpeller in the direction of movement;

FIG. 17B is a fragmentary sectional view showing the blades inclinedwith respect to an impeller opposite to the direction of movement;

FIG. 18 is a fragmentary axial section view showing a rotating diaphragmseal.

FIGS. 19 and 20 are axial section views showing the impeller bladesextending adjacent to a stationary wall.

Referring to FIG. 1 an embodiment of the invention is shown and isreferred to generally by the reference numeral 20. Pump 20 comprises apump casing 21 providing chamber 21a having an inlet 22 and outlet 23.Chamber 21a provides an open passage from inlet 22 to outlet 23.Impeller 24 is disposed adjacent side 21b of casing 21 facing towardchamber 21a and inlet 22. Impeller 24 comprises a plurality of radiallydisposed blades 25 extending from hub 26 in an outward direction (FIG.2). Blades 25 extend at substantially right angles to disc portion 24::of the impeller (FIG. 3). The side of impeller disc 24a opposite that towhich the blades are attached is provided with a plurality of backblades 27 which are adapted to control the pressure at the back side ofimpeller 24 in order to minimize thrust loading of the impeller as wellas leakage at the impeller shaft. As shown in FIG. 1 the profile of hub26 and impeller disc 24a is a curved section extending across theimpeller between vanes 25. In addition the depth of the blades increasesas the blades extend from the center. Casing 21 further includesstationary shroud ring 28 which surrounds the periphery of the impelleradjacent the free ends of blades 25.

When fluid is admitted into pump 2! and impeller 24 is set into rotarymotion, the fluid between blades 25 is accelerated outwardly in a radialdirection between the blades toward stationary shroud ring 28 which isof a substantially cylindrical form surrounding the free ends of theblades. Since shroud ring 28 intersects the outward radial path of flowof the fluid between blades 25, the shroud ring serves as a means fordiverting the movement of the outwardly flowing fluid thereby reversingit so that it is deflected inwardly toward the axis of impeller 24. Theoutward flow of the fluid between the blades and the subsequentreturning flow of the fluid results in a recirculation of the fluidbeing established with respect to the impeller. The velocity of thefluid circulating adjacent to the impeller forms effectively a fluidbarrier in front of the impeller which reduces the possibility offoreign substances in the fluid from striking the impeller. The higherpressure accompanying the diverting of the flow by shroud ring 28 servesto assist the fluid to flow back toward the axis of the impeller so thata major portion of the outward flow between the blades is subsequentlyreturned toward the axis of the impeller.

Once the recirculation has been established about the impeller, the flowpattern of the recirculation eifectively forms a torus-like flow offluid having fluid blades or lobes of moving fluid as the toroidal flowpasses over the edges of the blades. The fluid blades or lobes formed bythe recirculation couple to the remaining portion of the fluid inchamber 21a of the casing and drive it in a rotary motion so that flowis maintained from inlet 22, through chamber 21a and to outlet 23. Thefluid blades or lobes formed by the recirculation with respect to theblades of the impeller provide an intensive coupling to the volume offluid within chamber 210 of the casing. As a result of the coupling, thevolume of fluid within the passage formed by chamber 210 becomesaccelerated in a rotary direction. The rotating fluid in the chamberflows outwardly through outlet 23.

The flow passing from the inlet to the outlet is driven by therecirculation of fluid with respect to the impeller so that the flowthrough the pump need not intersect the blades of the impeller with theexception of the fluid involved in the recirculation. This flowarrangement is of great advantage when foreign material is carried inthe fluid since it tends to prevent contact of the foreign material withthe impeller. The pump produces a vortex which extends from inlet 22back along pipe 29 due to the whirl of the fluid in chamber 21a. Inlet22 may be pro vided with contraction 22b extending from location 22a to22b which serves to increase the relative velocity of the fluid passingthrough the contraction and causes foreign substances to be thrownoutwardly within chamber In so that the impeller is not contacted. Thediffusing section between locations 22b and 220 facilitates the outwardflow as the fluid enters chamber 21a. The relative velocity of the fluidthrough the pump can be maintained substantially constant until thefluid approaches outlet 23. In the transition from rotary flow to flowin the direction of the outlet, the relative velocity can increase asthe flow advances from the interior of the casing into outlet 23.

The rotation of the impeller within the confines of shroud ring 28serves to center the impeller'with respect to the shroud ring due to thecushioning elfect of the layer of fluid between the end portions 25a ofblades 25 and the inside surface of the shroud ring. This arrangementand the fact that the impeller is substantially in the wall of thecasing which reduces the degree of overhang of the impeller shaftresults in only moderate loading upon th shaft bearings.

In order to reduce frictional eifects of the circulating fluid adjacentimpeller blades 25, edges 25b of the blades which face the interior ofcasing 21 can be provided with sharpened edges. In FIG. 3 the arrowindicates the direction of motion of the blades. Similarly, to reducethe fluid friction at free ends 25a of the blades, this portion of theblades can also be provided with sharpened edges as shown in FIG. 4Where the arrow also indicates the direction of rotation of the vanes.

In the embodiment of FIG. 5A, to facilitate the return of the fluidmoving radially outwardly along the impeller between blades 25, casing30 and support 31, are provided with curved recess or shroud ring 32adjacent to curved ends 33a of blades 33. On the other hand as shown inFIG. 6A, impeller 34 is provided with a rotating shroud 35 having acurved recess 35:: adjacent to curved ends 36a of blades 36. In thisarrangement stationary shroud ring 28 attached to casing 21 surroundsthe periphery of rotating shroud ring 35. Similarly as in thearrangement in FIG. 5A curved recess 35a facilitates the return flow ofthe recirculating fluid adjacent to blades 36 of impeller 34.

In a further embodiment of the pump shown in FIG. 7, impeller 37 isprovided with rotating shroud 38 similar to that of FIG. 6A and bladering 39 which intersects each of the blades 40. The toroidal-like bladering 39 forms curved passages 41 shown in FIGS. 7 and 8 which positivelydirect the flow of fluid from the axis of impeller 37 into a curved pathwhich results in the fluid being returned toward the center of theimpeller as it leaves the passage adjacent the periphery of theimpeller.

Impeller 42 can be located in a portion of chamber 43a Within casing 43(FIG. 15A). In this arrangement impeller 42 is provided with rotatingshroud ring 44 which includes a curved recess 44a adjacent to curvedends 45a of blades 4-5. In this construction in order to provide thefluid centering-eifect for impeller 42 and to prevent excessive leakagepast the impeller, the periphery 42a of the impeller is disposed withinthe cylindrical section of stationary shroud ring 43a adjacent to thecasing.

In FIG. 2 blades 25 extend in a substantially radial direction. In apump having low specific rotary speeds forward-curved blades 46 ofimpeller 45 can be used (FIG. 9). At high specific rotary speedsbackwardcurved blades 33b can be used (FIG. 5B).

By way of example a pump of the type shown in FIGS. 1 and 2 can includechamber 21a with an axial dimension of approximately 3 inches. In suchan example stationary shroud 25a surrounding the impeller would have aninside diameter of approximately 5 /2 inches. The axial dimension of theshroud would be approximately 2 inches. The inside diameter of casing 21of such a pump would be approximately 8 /2 inches and its axial widthapproximately 3 inches. The axial dimension of blade 25 between itsradial free edge and the surface of disc 24a would be approximately 1 /2inches. The inside diameters of contraction 22b and the pipe at inlet 22are approximately 3, 2, and 4 inches, respectively. In the pump of theexample the impeller has 8 blades.

To obtain the improved coupling of the recirculating fluid adjacent theimpeller with the fluid in chamber 210, it is necessary that the fluidblades extend adjacent to the free radial edges of blades 25. When pumpssmaller than the example set forth are to be provided and the axialdimension of chamber 21a is reduced, the impeller may be provided with agreater number of blades so that the recirculating fluid does not extendacross the entire passage of chamber 21a but instead extends in a mannersuiticient only to engage the portion of the fluid in the passageadjacent to the impeller. To decrease the extent to which therecirculating fluid projects beyond the impeller, a greater number ofimpeller blades can be employed thereby reducing the width of thepassage between them and at the same time reducing the size of therecirculating torus-like flow of fluid adjacent the impeller. Similarlythe axial dimension of blades 25 with respect to disc 24a can be varieddependent upon the size of the impeller and its rotary speed to insurethat the recirculating fluid extends adjacent to the free radial edgesof the blades and is conditioned to engage or couple the fluid withinthe passage of chamber 21a.

During operation the fluid adjacent the free ends of blades 25 and thestationary shroud ring 25a experiences a build-up of pressure due to thediverting action of the shroud ring which directs the outward radialflow to return toward the axis of the impeller. At the same time thefluid in the clearance area provides the fluid centering effectpreviously discussed.

In a modification of the pump shown in FIGS. 1 and 2, outlet 23 isdisposed in a radial direction with respect to casing 21. In anadditional modification of the pump, outlet 23 is inclined with respectto the axis of rotation of impeller 24.

In FIG. there is shown an embodiment of the pump having a substantiallytapered casing 48 and tapered impeller 49. Blades 50 extend from hub 52of the impeller adjacent to its axis of rotation to curved ends 500which are adjacent the stationary shroud ring formed by portion 48:: ofthe casing and portion 51a of support 51. The tapered form of casing 48results in passage 48b having a tapered form which simplifies, reducesthe angularity of the flow pattern from inlet 53 and past impeller 49with the result that the tendency of foreign substances in the fluid tostrike the impeller is substantially eliminated.

As previously discussed, the curved form of shroud rings 48a and 51aprovides means for reversing the movement of fluid between blades 50 sothat it returns toward hub 52 of impeller 49. This arrangement insuresthat the proper degree of circulation is established adjacent to theimpeller so that the fluid passing into casing 48 is suflicientlycoupled by the fluid blades or lobes formed during the process ofrecirculation with respect to the impeller.

In FIG. 3 blades 25 are shown disposed at substantially right angles tothe plane of impeller disc 24a while in FIG. 17A, blades 54 are inclinedat an angle in the direction of motion with respect to impeller disc 55.On the other hand as shown in FIG. 17B, vanes 66 can be inclined at anangle opposite to that of the direction of motion with respect to disc57. In each form the tapered section adjacent to the edge blade reducesfluid friction and cavitation effects.

In FIG. 11A another embodiment of the invention is shown in which thecasing and the impeller are of a substantially hollow cylindrical form.The casing of pump 58 includes sleeves 59 attached at each end tocylindrical impeller 60. Sleeves 59 are supported in rotation bybushings 61 at each end of the impeller and the bushings in turn aresupported by housing 62. In the embodiment shown in FIG. 11A, impeller60 also serves as the rotor of the electrical motor for driving thepump. The motor includes stator windings 63 disposed about stator 64.Windings 65 can be applied about cylindrical impeller or rotor 60. Alongthe inner surface of rotor 66 there are disposed in a radial manner withrespect to the axis of rotation, a plurality of blades 66. Each of theblades has a curved end portion 660. The portion of the rotor adjacentto the curved end portions of the blades is formed into rotating shroud67 having a curved recess. Upon rotation of the cylindrical impeller 60,the fluid is accelerated along the radially extending Wall betweenblades 66 in the direction of their curved end portions 66a. At thispoint rotating shroud 67 serves as a means for diverting the movement ofthe fluid so that it is substantially returned to the location fromwhich its motion initiated. The result of the reversing flow is toinstitute a recirculation of the fluid with respect to blades 66similarly as discussed with respect to the other embodiments of thepump. The recirculation causes the formation of fluid blades or lobeswhich couple to the fluid passing through the chamber. The coupling tothe fluid causes it to rotate and advance so that the fluid movesfrom'inlet 68 through the chamber to outlet 69 with a screw-like motion.

Various embodiments of the pump of the present invention can be employedas a fluid motor by supplying a flow of fluid to the pump inlet. Themovement of the fluid through the casing initiates movement of theimpeller after which the rotation of the impeller establishes therecirculation of fluid with respect to the impeller. The fluid blades ofthe recirculation then form an eflective coupling with the flow of fluidthrough the passage with the result that efficient operation isobtained.

In industrial processes it may be necessary to pump a fluid or toagitate a fluid in a substantially closed system. For example inremoving foreign substances from a fluid or in separating a givenmaterial from a fluid, it is customary to centrifuge the fluid in aclosed chamber. The apparatus of the present invention is adaptable toserve as a means for rotating or agitating the fluid in such anapparatus. Here the impeller and the means for diverting the flow offluid from the impeller to establish recirculation are disposed within aclosed chamber and operated in order to establish the coupling with thefluid in the chamber. With this arrangement the fluid in the chamber isrotated by the coupling action and the resulting angular velocityaccelerates the particles suspended in the fluid so that they can beseparated from the fluid in the radial direction. For these purposes thechamber can be formed in the manner that is normally used for cycloneseparators.

In FIG. 12 there is shown one embodiment of a seal arrangement adaptedfor the pump of the invention. Impeller 70 is mounted upon stepped shaft71 which in turn is supported by roller bearing 72. The roller bearingis mounted within housing 74. Sealing ring 73 is secured to shaft 71between the impeller and the roller bearing. About inner hub 25% of theimpeller there is mounted sealing collar 79. Seal 78 which is formedfrom known material suited for this purpose such as rubber, plasticmaterial, carbon, ceramic material, hard metal and the like, issupported by membrane 77 which is attached to support ring 76 mounted inhousing 74. Membrane 77 which can be fabricated from material such asrubber, plastic, thin metal, etc., is corrugated so that it is free todeflect in both a radial and axial direction when subjected to fluidpressure along its surface. Back blades 31 disposed along the rearsurface of impeller 76 are employed to control the pressure level withinchamber 32 adjacent to the membrane seal. With a positive pressure onthe impeller side of membrane 77, the membrane urges seal 78 radially inthe direction of shaft 71 when the seal can be radially deformed andaxially in the direction of bearing 72. The result of these combinedforces is to urge seal 7 8 against surface 79a of the sealing collar andsurface 73a of the sealing ring. Upon an in crease in pressure withinchamber 82, the seal is urged with greater force against the adjacentsurfaces so that the increase contact pressure provides more effectivesealing.

Another embodiment of a seal adapted for the pump of the invention isshown in FIG. 16A. Impeller 83 is mounted upon shaft 84 which issupported by ball bearing 85, mounted in housing 86. Oil seal 87 mountedin housing 36 engages sleeve 88 and thereby prevents the escape oflubricant from the bearing. Support 89 for rotating seal 91) is mountedupon shaft 84 between sleeve 83 and sleeve 91 which is adjacent toimpeller 83. Stationary seal 92 is supported in engagement with the faceof rotating seal 90 by means of diaphragm support 93 which is attachedat its outer periphery to housing 86. Diaphragm support 93 comprisesdiaphragm spring 94 (FIG. 1613) with covering 95 of a flexible materialsuch as natural rubber, synthetic rubber, plastic and the like,vulcanized or molded about the diaphragm spring.

If impeller 83 is provided with relief openings 83a, the pressure incavity 96 behind impeller 83 can be below atmospheric pressure. Withthis condition the reduced pressure causes diaphragm assembly 93 to beurged toward the impeller thereby reducing the pressure upon the sealduring operation. The effect of this condition can be minimized byemploying diaphragm assembly 93 in which diaphragm spring 94 in its restposition before assembly into the pump extends or deflects towardbearing 85. The deflection of the spring urges the diaphragm assemblyinto a cone-like shape. During assembly of the pump, the diaphragm ispreloaded to take substantially the form shown in FIG. 16A. In thismanner stationary seal 92 is preloaded against rotating seal 91). Duringoperation a negative pressure condition within cavity 96 merely reducesthe degree of preload but does not reduce it below a value at which aneffective seal is still maintained.

For the case where the pressure in cavity 96 increases during operation,the diaphragm is urged in the direction of bearing 85 with the resultthat stationary seal 92 is urged with increasing force against rotatingseal 90. With such an arrangement the sealing pressure increases as thepressure in cavity 96 increases so that leakage can be prevented or heldto a satisfactory level for all pressure conditions of the pump.

In FIG. 13 diaphragm seal assembly 97 is initially deflected in aconical manner toward bearing 98 which supports shaft 99 upon whichimpeller is mounted. It is therefore possible upon assembly of the pumpto preload stationary seal 101 against rotating seal 10?; mounted withinseal support 103 which is secured to shaft 99. During operation if areduced pressure exists within cavity 104 behind impeller 10%, thediaphragm seal assembly is urged toward the impeller. Under such acondition diaphragm spring 105 within assembly 97 offers an increasingresistance to the movement toward the impeller. Consequently thisarrangement enables the pressure between the stationary and rotatingseals to be confined to a predetermined range.

In FIG. 18 another seal arrangement suitable for the pump of the presentinvention is shown. Here diaphragm seal assembly 105 is attached bymeans of support ring 107 to rotate with shaft 1138 upon which impeller1119 is mounted. At the periphery of the assembly there is attachedrotating seal 119 which engages stationary seal 111 supported by housing112. The assembly contains diaphragm spring 113 similar to that shown inFIG. 1613. The effect of pressure in cavity 114 is similar to thatpreviously discussed. However since the seal assembly rotates, it isalso subjected to the effects of centrifugal force during operation.Centrifugal force applied to diaphragm assembly 196 causes rotating seal110 to be urged with increasing force against stationary force 111 asthe shaft speed increases. Consequently the greater the pump speed, thegreater the force at the seals so that increasing pressures in cavity114 are prevented from causing excessive leakage.

For the case where it is desirable to reduce the sealing pressure duringoperation, for example, to prevent excessive wear of the seals at highsurface speeds accompanying high rotational speeds, the stationary sealcan be placed on side 110a of the rotating seal as seen in FIG. '18 withthe result that as the diaphragm assembly is subjected to increasingrotating speeds and increasing centrifugal force, the pressure betweenthe seals reduces.

Still another seal adapted for the pump of the present invention isshown in FIG. 14. Impeller 115 is mounted upon shaft 116 and secured bynut 117. At the side of the impeller 115 adjacent cavity 113 behind theimpeller there is mounted sealing ring 119 which rotates with theimpeller. Seal 120 is mounted in seal housing 121 which is supportedwithin sleeve 122 engaged with housing 123. Pin 124 prevents anyrotation of seal housing 121. Washer-type springs 125 disposed adjacentto seal housing 121 urge it toward the impeller thereby preloading seal121) against sealing ring 119. Slot 126 in seal housing 121 enables theaxial motion of the seal housing to take place with respect to pin 124.

The seal arrangement shown in FIG. 16A is especially suitable to thepump of the invention. The pressure changes within cavity 96accompanying changes in pump flow are relatively small as compared withthose of a centrifugal pump. This characteristic in conjunction with thefunction of the impeller back blades enables the pressure in cavity 96to be maintained within a limited range. Therefore the load applied bydiaphragm assembly 93 to stationary seal 92 and transmitted to rotatingseal 91 can also be maintained within a limited range. Thus leakage canbe prevented without undue seal Wear.

It should be understood that the various embodiments of the seals arealso adaptable for rotating machinery other than pumps. These shaftswhich are subjected to an adjacent pressure condition or leakage problemof either the working fluid or of lubricating material can be providedwith one or more of such seals.

While there has been disclosed what at present are considered to bepreferred embodiments of the invention, it is to be understood that manychanges and modifications may be made therein without departing from theessential spirit of the invention. It is intended therefore in theappended claims to cover all such changes and modifications within thetrue scope of the invention.

An example of a change or modification to the invention is shown inFIGS. 19 and 20. Impeller 131} includes a plurality of blades 131radially extending from hub 132. The impeller does not include animpeller disc or rotating wall adjacent the blades but instead theblades extend radially free of one another. At the peripheral portion ofthe impeller there is disposed rotating shroud 127 which is mountedalong the tips of blades 131. Stationary wall 128 extends radially fromthe axis of rotation of impeller shaft 129 and is disposed adjacentblades 131 of the impeller. During operation the fluid flows radiallyand in an outward direction along wall 128 and between blades 131.Shroud 127 diverts the flow so that recirculation takes place.

In FIG. 20, blades 133 of impeller 134 extend radially from hub 135 andagain there is no impeller disc or rotating wall adjacent the blades.Instead, stationary wall 136 extends radially from the axis of rotationof the impeller and adjacent to the blades. Stationary shroud 137 isdisposed about the periphery of the impeller. During operation the flowpasses in a radial outward direction along stationary wall 136 andbetween the blades. Stationary shroud 137 diverts the outward flow andcauses the flow to recirculate with respect to the impeller.

I claim:

1. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spacedfrom the plane of the portion of said structure disposedopposite thereto to form a lateral clearance extending between all ofsaid portion of the impeller and said plane of said portion of thestructure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, and stationary means extending in a substantiallylateral direction about the entire periphery of said impeller andlocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

2. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom at substantially a right angle and blades extendinglaterally from said wall and at an angle with respect to its rotatingdirection and rotating therewith, structure forming a chamber laterallyoffset from said wall and entirely open thereto and to all of its saidblades and to full circumferential flow and adapted to confine fluidwith said wall and blades immersed therein, the portion of said impellerfacing said chamber being laterally spaced from the plane of the portionof said structure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and stationary means extendingin a substantially lateral direction about the entire periphery of saidimpeller and located contiguous to and substantially enclosing said endsof the blades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths oflset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

3. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom with a substantially tapered form and bladesextending laterally from said wall and at an angle with respect to itsrotating direction and rotating therewith, structure forming a chamberlaterally offset from said wall and entirely open thereto and to all ofits said blades and to full circumferential flow and adapted to confinefluid with said wall and blades immersed therein, rotation of saidimpeller normally causing said blades to force said fluid to flow in theradially extending direction of said wall lengthwise with respect tosaid blades while rotating in their rotating direction and to bedischarged from the blades ends extending in said direction, and meanslocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

4. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom with an elongated form and blades extending laterallyfrom said wall and at an angle with respect to its rotating directionand rotating therewith, structure forming a chamber laterally oifsetfrom said wall and entirely open thereto and to all of its said bladesand to full circumferential flow and adapted to confine fluid with saidwall and blades immersed therein, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and means located contiguous toand sub stantially enclosing said ends of the blades for diverting saidfluid in a direction causing at least a substantial portion thereof toflow reversely toward the other ends of said blades in paths offset fromthe flow in said radially extending direction of said wall between thelatter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

5. A device including a rotary impeller having an axis about which itrotates and forming a disc-shaped wall rotating about said axis andextending radially therefrom and blades extending laterally from saidwall and at an angle with respect to its rotating direction and rotatingtherewith, structure forming a chamber laterally olfset from said walland entirely open thereto and to all of its said blades and to fullcircumferential flow and adapted to confine fluid with said wall andblades immersed therein, the portion of said impeller facing saidchamber being laterally spaced from the plane of the portion of saidstructure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and stationary means extendingin a substantially lateral direction about the entire periphery of saidimpeller and located contiguous to and substantially enclosing said endsof the blades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths olfset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from out- 13 sideof said chamber to the flow established by said fluid torus and topermit this flow to discharge to said outside.

6. A device including a rotary impeller having an axis about which itrotates and forming a substantially conically-shaped wall rotating aboutsaid axis and extending radially therefrom and blades extendinglaterally from said wall and at an angle with respect to its rotatingdirection and rotating therewith, structure forming a chamber laterallyoffset from said wall and entirely open thereto and to all of its saidblades and to full circumferential flow and adapted to confine fluidwith said wall and blades immersed therein, rotation of said impellernormally causing said blades to force said fluid to flow in the radiallyextending direction of said wa l lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and means located contiguous toand substantially enclosing said ends of the blades for diverting saidfluid in a direction causing at least a substantial portion thereof toflow reversely towards the other ends of said blades in paths offsetfrom the flow in said radially extending direction of said wall betweenthe latter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

7. A device including a rotary impeller having an aixs about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall andsubstantially radially with respect to said axis, said blades rotatingwith said wall, structure forming a chamber laterally offset from saidwall and entirely open thereto and to all of its said blades and to fullcircumferential flow and adapted to confine fluid with said wall andblades immersed therein, the portion of said impeller facing saidchamber being laterally spaced from the plane of the portion of saidstructure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and stationary means extendingin a substantially lateral direction about the entire periphery of saidimpeller and located contiguous to and substantially enclosing said endsof the blades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a toruslike flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

8. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall andsubstantially radially with respect to said axis, said blades rotatingwith said wall and being curved along their length, structure forming achamber laterally offset from said wall and entirely open thereto and toall of its said blades and to full circumferential flow and adapted toconfine fluid with said wall and blades immersed therein, rotation ofsaid impeller normally causing said blades to force said fluid to flowin the radially extending direction of said wall lengthwise with respectto said blades While rotating in their rotating direction and to bedischarged from the blades ends extending in said direction, and meanslocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

9. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,said blades being curved along their length, structure forming a chamberlaterally offset from said wall and entirely open thereto and to all ofits said blades and to full circumferential flow and adapted to confinefluid with said wall and blades immersed therein, rotation of saidimpeller normally causing said blades to force said fluid to flow in theradially extending direction of said wall lengthwise with respect tosaid blades while rotating in their rotating direction and to bedischarged from the blades ends extending in said direction, and meanslocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to perrnitthis flow to discharge to said outside.

10. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending perpendicularly from said walland at an angle with respect to its rotating direction and rotatingtherewith, structure forming a chamber laterally offset from said walland entirely open thereto and to all of its said blades and to fullcircumferential flow and adapted to confine fluid with said wall andblades immersed therein, the portion of said impeller facing saidchamber being laterally spaced from the plane of the portion of saidstructure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and stationary means extendingin a substantially lateral direction about the entire periphery of saidimpeller and located contiguous to and substantially enclosing said endsof the blades for diverting said fluid in a direction causing 1 at leasta substantial portion thereof to flow reversely towards the other endsof said blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally wth respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

11. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to from a lateral clearance extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, each of said blade ends having edge portions disposedat substantially right angles to the length of the blade, and stationarymeans extending in a substantially lateral direction about the entireperiphery of said impeller and located contiguous to and substantiallyenclosing said ends of the blades for diverting said fluid in adirection causing at least a substantial portion thereof to flowreversely towards the other ends of said blades in paths offset from theflow in said radially extending direction of said wall between thelatter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

12. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, rotation of said impeller normally causing said blades to forcesaid fluid to flow in the radially extending direction of said walllengthwise with respect to said blades while rotating in their rotatingdirection and to be discharged from the blades ends extending in saiddirection, said blade ends being curved in the direction of said wall,and means located contiguous to and substantially enclosing said ends ofthe blades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

p 13. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a substantially cylindrical chamber laterally offsetfrom said wall and entirely open thereto and to all of its said bladesand to full circumferential flow and adapted to confine fluid with saidwall and blades immersed therein, the portion of said impeller facingsaid chamber being laterally spaced from the plane of the portion ofsaid structure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, and stationary means, extendingin a substantially lateral direction about the entire periphery of saidimpeller and located contiguous to and substantially enclosing said endsof the blades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a toruslike flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in eflect a fluid impeller engaging the fluid insaid chamber, said structureforming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

14. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a substantially tapered chamber laterally offset fromsaid wall and entirely open thereto and to all of its said blades and tofull circumferential flow and adapted to confine fluid with said walland blades immersed therein, rotation of said impeller normally causingsaid blades to force said fluid to flow in the radially extendingdirection of said wall lengthwise with respect to said blades whilerotating in their rotating direction and to be discharged from theblades ends extending in said direction, and means located contiguouslyto and substantially enclosing said ends of the blades for divertingsaid fluid in a direction causing at least a substantial portion thereofto flow reversely towards the other ends of said blades in paths offsetfrom the flow in said radially extending direction of said wall betweenthe latter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respecttively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

15. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming an elongated chamber laterally offset from said walland entirely open thereto and to all of its said blades and to fullcircumferential flow and adapted to confine fluid with said wall andblades immersed therein, rotation of said impeller normally causing saidblades to force said fluid to flow in the radially extending directionof said wall lengthwise with respect to said blades while rotating intheir rotating direction and to be discharged from the blades endsextending in said direction, and means located contiguous to andsubstantially enclosing said ends of the blades for diverting said fluidin a direction causing at least a substantial portion thereof to flowreversely towards the other ends of said blades in paths offset from theflow in said radially extending direction of said wall between thelatter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in eflect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

16. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to form a lateral clearance extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, the dimension of the outer portions of said chamber beinggreater than the dimension of the outer portions of said impeller,rotation of said impeller normally causing said blades to force saidfluid to flow in the radially extending'direction of said walllengthwise with respect to said blades while rotating in their rotatingdirection and to be discharged from the blades ends extending in saiddirection, and stationary means extending in a substantially lateral diection about the entire periphery of said impeller and locatedcontiguous to and substantially enclosing said ends of the blades fordiverting said fluid in a direction causing at least a substantialportion thereof to flow reversely towards the other ends of said bladesin paths offset from the flow in said radially extending direction ofsaid wall between the latter flow and fluid in said chamber, to form atorus-like flow of fluid rotating about said axis while flowingrecircuitingly continuously laterally with respect to its rotation andforming in effect a fluid im peller engaging the fluid in said chamber,said structure forming a fluid inlet and outlet for said chamberrespectively located to permit fluid to feed from outside of saidchamber to the flow established by said fluid torus and to permit thisflow to discharge to said outside.

17. A device including a rotary impeller having'an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to form a lateral clearance'extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rot-ating in theirrotating direction and'to be discharged from the blades ends extendingin said directiomand stationary means extending in a substantiallylateral direction about the entire periphery of said impeller andlocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely to wards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said Wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and'forming in effect a fluid impeller engaging the fluid insaid chamber, said diverting means comprising a shroud member, saidstructure forming a fluid inlet and outlet for said chamber respectivelylocated to permit fluid to feed from outside of said chamber to the flowestablished by said fluid torus and to permit this flow to discharge tosaid outside. 7

18. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the por tion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to form a lateral clearance extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, and stationary means extending in a substantiallylateral direction about the entire periphery of said impeller andlocated contiguous' to and substa'ntially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely to- Wards the other endsof said blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, tofor m a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterallywith respect to'itsrotation and forming in eflect a fluid impeller engaging the fluid insaid chamber, said diverting means comprising a shroud member, thesurface portion of said shroud member contiguous to and substantiallyenclosing each of said blades ends being substantially perpendicularthereto, said structure forming a fluid inlet and out let for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow estab lished by said fluid torus and to permitthis flow to discharge to said outside.

19. A device including a rotary impeller having an axis about which'itrotates and forming a wall rotating about said axis and extendingradiallytherefrom and blades extending laterally from said wall and atan angle with re} spect to its rotating direction" and rotatingtherewith; structure forming a chamber laterally offset from said walland entirely open theerto and to all of its said blades and to fullcircumferential flow and adapted to confine fluid with said'wall andblades immersed therein, rota tion of said impeller norm-ally causingsaid blades to force said fluid to flow in the radially extendingdirection of said wall lengthwisewith respect to said blades whilerotating in their rotating direction and to be discharged from theblades ends extending in said direction, and means located contiguous toand substantially enclosing said ends of the blades for diverting saidfluid in a direction causing at least a substantial portion thereof toflow reversely towards the other ends of said blades'in paths offsetfrom the flow in said radially extending direction of said wall betweenthe latter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said diverting meanscomprising a shroud member disposed contiguous to said blades ends andhaving a continuous channel adjacent thereto, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

20. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structure disposed opposite thereto to form a lateral clearance extending between allof said portion of the impeller and said plane of said portion of thestructure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, stationary means extending in a substantially lateraldirection about the entire periphery of said impeller and locatedcontiguous to and substantially enclosing said ends of the blades fordiverting said fluid in a direction causing at least a substantialportion thereof to flow reversely towards the other ends of said bladesin paths offset from the flow in said radially extending direction ofsaid wall between the latter flow and fluid in said chamber, to form atoruslike flow of fluid rotating about said axis while flowingrecircuitingly continuously laterally with respect to its rotation andforming in effect a fluid impeller engaging the fluid in said chamber,said structure forming a fluid inlet and outlet for said chamberrespectively located to permit fluid to feed from outside of saidchamber to the flow established by said fluid torus and to permit thisflow to discharge to said outside, and means for accelerating the flowof fluid adjacent said fluid inlet.

21. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally offset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said Wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to form a lateral clearance extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, rotation of said impeller normally causing said blades-to force said fluid flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, stationary means extending in a substantially lateraldirection about the entire periphery of said impeller and locatedcontiguous to and substantially enclosing said ends of the blades fordiverting said fluid in a direction causing at least a substantialportion thereof to flow reversely towards the other ends of said bladesin paths offset from the flow in said radially extending direction ofsaid wall between the latter flow and fluid in said chamber, to form atorus-like flow of fluid rotating about said axis while flowingrecircuitingly continuously laterally with respect to its rotation andforming in effect a fluid impeller engaging the fluid in said chamber,said structure forming a fluid inlet and outlet for said chamberrespectively located to permit fluid to feed from outside of saidchamber to the flow established by said fluid torus and to permit thisflow to discharge to said outside, and means for accelerating the flowof fluid adjacent said fluid inlet, said accelerating means comprising aflow constriction disposed adjacent to said inlet.

22. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom and blades extending laterally from said wall and atan angle with respect to its rotating direction and rotating therewith,structure forming a chamber laterally oflset from said wall and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said wall and blades immersedtherein, the portion of said impeller facing said chamber beinglaterally spaced from the plane of the portion of said structuredisposed opposite thereto to form a lateral clearance extending betweenall of said portion of the impeller and said plane of said portion ofthe structure, rotation of said impeller normally causing said blades toforce said fluid to flow in the radially extending direction of saidwall lengthwise with respect to said blades while rotating in theirrotating direction and to be discharged from the blades ends extendingin said direction, said wall and said blades forming a plurality ofchannels through which said flow in the radially extending directionlengthwise with respect to said blades passes, the depth of each of saidWall channels increasing along the length thereof in the direction ofsaid blades ends, and stationary means extending in a substantiallylateral direction about the entire periphery of said impeller andlocated contiguous to and substantially enclosing said ends of theblades for diverting said fluid in a direction causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths offset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a toruslike flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by said fluid torus and to permitthis flow to discharge to said outside.

23. A device including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom, said impeller having a central hub and bladesextending laterally from said wall and at an angle with respect to itsrotating direction and rotating therewith, structure forming a chamberlaterally offset from said wall and entirely open thereto and to all ofits said blades and to full circumferential flow and adapted to confinefluid with said wall and blades immersed therein, rotation of saidimpeller normally causing said blades to force said fluid to flow in theradially extending direction of said wall lengthwise with respect tosaid blades while rotating in their rotating direction and to bedischarged from the blades ends extending in said direction, said walland said blades forming a plurality of channels through which said flowin the radially extending direction lengthwise with respect to saidblades passes, the depth of each of said channels increasing along thelength thereof in a direction extending outwardly from adjacent saidhubto a predetermined depth, and means located contiguous to andsubstantially enclosing said ends of the blades for diverting said fluidin a direction causing at least a substantial portion thereof to flowreversely towards the other ends of said blades in paths offset from thelow in said radially extending direction or" said wall between thelatter flow and fluid in said chamber, to form a torus-like flow offluid rotating about said' axis while flowing recircuitin lycontinuously laterally with respect to its rotation and forming ineffect a fluid impeller engaging the fluid in said chamber, saidstructure forming a fluid inlet and outlet for said chamber respectivelylocated to permit fluid to feed from outside of said chamber to the flowestablished by said fluid torus and to permit this flow to discharge tosaid outside.

24. A device including a rotary impeller having an axis about which itrotates and a substantially tapered body portion rotating about saidaxis and extending angularly therefrom and blades extending laterallyfrom said body portion at an angle with respect to its rotatingdirection and rotating therewith, structure forming a substantiallytapered chamber laterally offset from said body portion and entirelyopen thereto and to all of its said blades and to full circumferentialflow and adapted to confine fluid with said body portion and bladesimmersed therein, rotation of said impeller normally causing said bladesto force said fluid to flow in the angularly extending direction of saidbody portion lengthwise with respect to said blades while rotating intheir rotating direction and to be discharged from the blades ends extending in said direction, and means located contiguous to'andsubstantially enclosing said ends of the blades for diverting said fluidin a direction causing at least a substantial portion thereof to flowreversely towards the other ends of said blades in paths oflset from theflow in said angularly extending direction of said body portion betweenthe latter flow and fluid in said chamber, to form a torus-like fl w or"fluid rotating about said axis while flowing recircuitingly continuouslylaterally with respect to its rotation and forming in effect a fluidimpeller engaging the fluid in said chamber, said structure forming afluid inlet and outlet for said chamber respectively located to permitfluid to feed from outside of said chamber to the flow established bysaid fluid torus and to permit this flow to discharge to said outside.

25. A pump comprising a pumping chamber adapted to receive fluid to bepumped, a rotary impeller disposed adjacent to the inner surface of saidchamber, the portion of said impeller facing said chamber beinglaterally spaced from the portion of said chamber disposed oppositethereto to form a lateral clearance extending between all of saidportion of the impeller and said chamber, said impeller having a meansfor moving with respect to said impeller the portion of fluid in saidchamber adjacent said impeller, said moving means substantially facingthe interior portion of said chamber, and stationary means extending ina substantially lateral direction about the entire periphery of saidimpeller and contiguous to and substantially enclosing said moving meansfor substantially reversing said movement of said portion of fluid in adirection between said moving means and the other portion of said fluidin said chamber, said reversing means causing circulation of saidportion of fluid with respect to said moving means, whereby saidcirculation couples with and rotates said other portion of fluid to urgesaid other portion from said chamber.

26. A pump comprising a pumping chamber adapted to receive fluid to bepumped, a rotary impeller disposed adjacent to the inner surface of saidchamber, said impeller having a plurality of blades for causing movementtoward an end portion of each of said blades of the portion of fluid insaid chamber adjacent said blades, said blades substantially facing theinterior portion of said chamber, the portion of said impeller facingsaid chamber being laterally spaced from the portion of said chamberdisposed opposite thereto to form a lateral clearance extending betweenall of said portion of the impeller and said chamber, and stationarymeans extending in a substantially lateral direction about the entireperiphery of said impeller and contiguous to and substantially enclosingsaid end portion of said blades for substantially reversing saidmovement of said portion of fluid in a direction between said i'm pellerand the other portion of said fluid in said chamber, said reversingmeans causing recirculation of said portion of fluid with respect tosaid blades, whereby said recircu lation couples with and rotates saidother portion of fluid to urge said other portion from said chamber.

27. A device including a rotary impeller having an axis about which itrotates, a stationary wall extending radially from said axis, saidimpeller having blades rotating therewith adjacent said wall, saidblades extending laterally with respect to said wall and at an anglewith re spect to the rotating direction of said impeller, structureforming a chamber laterally offset from said Wall and entirely openthereto and to all of said blades and to full circumferential flow andadapted to confine fluid with said wall and blades immersed therein,rotation of said impeller normally causing said blades to force saidfluid to flow in the radially extending direction of said walllengthwise with respect to said blades while rotating in their rotatingdirection and to be discharged from the. blades ends extending in saiddirection, and means located contiguous to said ends of the blades fordiverting said fluid in a direction causing at least a substantialportion thereof to flow reversely towards the other ends of said bladesin paths offset from the flow in said radially extend ing direction ofsaid wall between the latter flow and fluid in said chamber, to form atorus-like flow of fluid rotating about said axis while flowingrecircuitingly con-' tinuously laterally with respect to its rotationand forming in eifect a fluid impeller engaging the fluid in saidchamher, said structure forming a fluid inlet and outlet for said'chamber respectively located to permit fluid to feed from outside ofsaid chamber to the flow established by saidfluid torus and to permitthis flow to discharge to said outside.

28. A device including a rotary impeller having an axis about which itrotates, a wall disposed about said axis and extending radiallytherefrom, said impeller hav-' ing blades extending laterally withrespect to said wall and at an angle with respect to the rotatingdirection of said impeller and rotating therewith, structure forming achamber laterally offset from said wall and entirely" open thereto andto all of said blades and to full circum-' ferential flow and adapted toconfine fluid with said wall and blades exposed thereto, the portion ofsaid impeller facing said chamber being laterally spaced from the planeof the portion of said structure disposed opposite thereto to form alateral clearance extending between all of said portion of the impellerand said plane of said portion of the structure, rotation of saidimpeller normally causing said blades to force said fluid to flow in theradially extending direction of said wall lengthwise with respect tosaid blades while rotating in their rotating direction and to bedischarged from the blades ends extending in said direction, and meansextending in a substantially lateral direction about the entireperiphery of said impeller and located contiguous to and substantiallyenclosing said ends of the blades for increasing the pressure of saidfluid adjacent thereto, the increase of pressure diverting said fluid ina direction extending toward the decrease in pressure of said fluidadjacent the central portion of said impeller and causing at least asubstantial portion thereof to flow reversely towards the other ends ofsaid blades in paths oflset from the flow in said radially extendingdirection of said wall between the latter flow and fluid in saidchamber, to form a torus-like flow of fluid rotating about said axiswhile flowing recircuitingly continuously laterally with respect to itsrotation and forming in effect a fluid impeller engaging the fluid insaid chamber, said structure forming a fluid inlet and outlet for saidchamber respectively located to permit fluid to feed from outside ofsaid 23 chamber to the flow established by said fluid torus and topermit this flow to discharge to said outside.

29. A pump including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom at substantially a right angle and blades extendinglaterally from said Wall and at an angle with respect to its rotatingdirection and rotating therewith, structure forming a chamber laterallyoffset from said wall and entirely open thereto and to all' of its saidblades and to full circumferential flow and adapted to confine fluidwith said wall and blades immersed therein, the portion of said impellerfacing said chamber being laterally spaced from the plane of the portionof said structure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, each of said ends of the bladeshaving an edge portion extending substantially parallel to said axis,and stationary means located contiguous to and substantially enclosingthe edge portion of each of said ends of the blades for diverting saidfluid to increase the pressure thereof, the diverting being in adirection causing at least a substantial portion thereof to flowreversely towards the other ends of said blades and the lower pressureadjacent thereto in paths offset from the flow in said radiallyextending direction of said wall between the latter flow and fluid insaid charn er, to form a torus-like flow of fluid rotating about saidaxis while flowing recircuitingly continuously laterally with respect toits rotation and forming in effect a fluid impeller engaging the fluidin said chamher, said diverting means comprising a circumferentialshroud member having its surface contiguous to and substantiallyenclosing the edge portion of each of said ends of the blades, saidstructure forming a fluid inlet and outlet for said chamber respectivelylocated to permit fluid to feed from outside of said chamber to the flowestablished by said fluid torous and to permit this flow to discharge tosaid outside.

30. A pump including a rotary impeller having an axis about which itrotates and forming a wall rotating about said axis and extendingradially therefrom at substantially a right angle and blades connectedadjacent one of their longitudinal edge portions to said wall andextending laterally therefrom at an angle with respect to its rotatingdirection and rotating therewith, structure forming a substantiallycylindrical chamber having spaced apart side portions and a central bodyportion, the longitudinal axis of said chamber being substantiallycoextensive with said axis, said chamber being laterally offset fromsaid wall and entirely open thereto and to all of its said blades and tofull circumferential flow and adapted to confine, fluid with said walland blades immersed therein, the portion of said impeller facing saidchamber being laterally spaced from the plane of the portion of saidstructure disposed opposite thereto to form a lateral clearanceextending between all of said portion of the impeller and said plane ofsaid portion of the structure, rotation of said impeller normallycausing said blades to force said fluid to flow in the radiallyextending direction of said wall lengthwise with respect to said bladeswhile rotating in their rotating direction and to be discharged from theblades ends extending in said direction, one of said side portionscontaining a recess havlng a longitudinal axis coextensive with saidaxis, said recess being adapted to receive said impeller and having asubstantially cylindrical wall disposed about said axis, said wall beingcontiguous to and substantially enclosing said ends of the blades, saidcylindrical Wall diverting said fluid to increase the pressure thereof,the diverting being in a direction causing at least a substantialportion thereof to flow rcversely towards the other ends of said bladesand the lower pressure adjacent thereto in paths offset from the flow insaid radially extending direction of said wall between the latter flowand fluid in said chamber, to form a torus-like flow of fluid rotatingabout said axis while flowing recircuitingly continuously laterally withrespect to its rotation and forming in elfect a fluid impeller engagingthe fluid in said chamber, said structure forming a fluid inlet andoutlet for said chamber respectively located to permit fluid to feedfrom outside of said chamber to the flow established by said fluid torusand to permit this flow to discharge to said outside.

References Cited by the Examiner UNITED STATES PATENTS Re. 24,803 3/60Burnside 103-115 X 1,627,294 5/27 Nydqvist l03-97 X 2,635,548 4/53Brawley 103103 2,724,338 11/55 Roth 103-103 2,824,520 2/58 Bartels 103-103 2,958,293 11/60 Pray 103 -103 FOREIGN PATENTS 719,353 4/42 Germany.808,796 7/51 Germany. 1,046,502 12/58 Germany.

420,324 4/47 Italy.

ROBERT M. WALKER, Primary Examiner.

LAURENCE V. EFNER, Examiner.

1. A DEVICE INCLUDING A ROTARY IMPELLER HAVING AN AXIS ABOUT WHICH ITROTATES AND FORMING A WALL ROTATING ABOUT SAID AXIS AND EXTENDINGRADIALY THEREFROM AND BLADES EXTENDING LATERALLY FROM SAID WALL AND ATAN ANGLE WITH RESPECT TO ITS ROTATING DIRECTION AND ROTATING THEREWITH,STRUCTURE FORMING A CHAMBER LATERALLY OFFSET FROM SAID WALL AND ENTIRELYOPEN THERETO AND TO ALL OF ITS SAID BLADES AND TO FULL CIRCUMFERENTIALFLOW AND ADAPTED TO CONFINE FLUID WITH SAID WALL AND BLADES IMMERSEDTHEREIN, THE PORTION OF SAID IMPELLER FACING SAID CHAMBER BEINGLATERALLY SPACED FROM THE PLANE OF THE PORTION OF SAID STRUCTUREDISPOSED OPPOSITE THERETO TO FORM A LATERAL CLEARANCE EXTENDING BETWEENALL OF SAID PORTION OF THE IMPELLER AND SAID PLANE OF SAID PORTION OFTHE STRUCTURE, ROTATION OF SAID IMPELLER NORMALLY CAUSING SAID BLADESWHILE FORCE SAID FLUID TO FLOW IN THE RADIALLY EXTENDING DIRECTION OFSAID WALL LENGTHWISE WITH RESPECT TO SAID BLADES WHILE ROTATING IN THEIRROTATING DIRECTION AND TO BE DISCHARGED FROM THE BLADES'' ENDS EXTENDINGIN SAID DIRECTION, AND STATIONARY MEANS EXTENDING IN A SUBSTANTIALLYLATERAL DIRECTION ABOUT THE ENTIRE PERIPHERY OF SAID IMPELLER ANDLOCATED CONTIGUOUS TO AND SUBSTANTIALLY ENCLOSING SAID ENDS OF THEBLADES FOR DIVERTING SAID FLUID IN A DIRECTION CAUSING AT LEAST ASUBSTANTIAL PORTION THEREOF TO FLOW REVERSELY TOWARDS THE OTHER ENDS OFSAID BLADES IN PATHS OFFSET FROM THE FLOW IN SAID RADIALLY EXTENDINGDIRECTION OF SAID WALL BETWEEN THE LATTER FLOW AND FLUID IN SAIDCHAMBER, TO FORM A TORUS-LIKE FLOW OF FLUID ROTATING ABOUT SAID AXISWHILE FORMING RECIRCUITINGLY CONTINUOUSLY LATERALLY WITH RESPECT TO ITSROTATION AND FORMING IN EFFECT A FLUID IMPELLER ENGAGING THE FLUID INSAID CHAMBER, SAID STRUCTURE FORMING A FLUID INLET AND OUTLET FOR SAIDCHAMBER RESPECTIVELY LOCATED TO PERMIT FLUID TO FEED FROM OUTSIDE OFSAID CHAMBER TO THE FLOW ESTABLISHED BY SAID FLUID TORUS AND TO PERMITTHIS FLOW TO DISCHARGE TO SAID OUTSIDE.